Axial limit means for male and female spline teeth in an orbital connection

ABSTRACT

Male and female spline teeth in an orbital connection between an orbital shaft and fluid pressure operating means are limited against relative axial movement by axial limit means comprising side member means held in facing relation to a side of said fluid pressure operating means. The side member means includes a shaft opening having a reference axis. The orbital shaft extends through said shaft opening and has a rotational movement about its own shaft axis and an orbital movement about said reference axis of said shaft opening. The side member means has stop wall means extending outwardly from said shaft opening. The orbital shaft has a shoulder with face wall means abuttably engaging the stop wall means to limit relative axial movement between the male and female spline teeth.

United States Patent Woodling [54] AXIAL LIMIT MEANS FOR MALE AND FEMALE SPLINE TEETH IN AN ORBITAL CONNECTION {72] Inventor: George V. Woodling, 22077 West Lake Road, Rocky River, Ohio 44116 [22] Filed: Dec. 15, 1970 [21] App]. No.: 98,396

1151 3,657,903 [451 Apr. 25, 1972 Primary Examiner-Edward G. Favors Attorney-Woodling, Krost, Granger & Rust [5 7] ABSTRACT Male and female spline teeth in an orbital connection between an orbital shaft and fluid pressure operating means are limited against relative axial movement by axial limit means comprising side member means held in facing relation to a side of said fluid pressure operating means. The side member means includes a shaft opening having a reference axis. The orbital shaft extends through said shaft opening and has a rotational movement about its own shaft axis and an orbital movement about said reference axis of said shaft opening. The side member means has stop wall means extending outwardly from said shaft opening. The orbital shaft has a shoulder with face wall means abuttably engaging the stop wall means to limit relative axial movement between the male and female spline teeth. 1

10 Claims, 8 Drawing Figures PATENTEDAPR 2 5 I972 am 34 as BACKGROUND OF THE INVENTION This application relates to my US. Pat. No. 3,549,283 and is directed to an improvement in the axial limit means, wherein the rubbing limit-surfaces, which limit the extent that the male and female spline teeth may axially move relative to each other, are changed to a new axial location where less relative orbital and rotational rubbing movements are encountered. The improvement is also directed to the fact that the rubbing-limit surfaces have a face-to-face contact instead of a peripheral, circumferential line-contact, wherein the wear qualities of the rubbing-limit surfaces are greatly improved.

Accordingly, it is an object of the present invention to position the rubbing-limit surfaces at a new axial location where less wear is encountered.

Another object is to provide a face-to-face contact between the rubbing-limit surfaces.

Another object is to make the tilt at which the rubbing-limit surfaces contact each other at a greater angle than the tilt of the orbital shaft.

SUMMARY OF THE INVENTION The invention constitutes axial limit means for male and female spline teeth which operate as connection means between an orbital shaft and fluid pressure operating means having a side face, said axial limit means limiting the. extent that said male and female teeth may axially move relative to each other and comprising side member means having first and second side wall means with said first side wall means held in facing relationship to said side face of said fluid pressure operating means, said second side wall means defining a reference plane, said side member means including a shaft opening extending therethrough, said shaft opening having a reference axis substantially perpendicular to said reference plane, said orbital shaft having an axis defining an orbital angle with respect to said reference axis and extending through said shaft opening, said orbital shaft having a rotational movement about its own shaft axis and an orbital movement about said reference axis, said side member means including stop wall means disposed outwardly of said shaft opening, body portion means extending outwardly of said orbital shaft and bodily disposed in said reference plane and being intersected thereby with a portion thereof leaning into said shaft opening, said body portion means including abuttable face wall means having a combined orbital and rotational movement relative to said stop wall means and disposed for abuttable engagement therewith to limit relative axial movement between said male and female spline teeth.

Other objects and a fuller understanding of this invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is an elongated, partial sectional view of an orbital fluid pressure device embodying the features of my invention;

FIG. 2 is a representation of a male shank provided on the terminal end portion of a hollow-shaft adapted to fit within a female socket of the rotary valve;

FIG. 3 is a view taken along the line 3--3 of FIG. 1, under the end cap, showing the stator-rotor mechanism;

FIG. 4 is a view taken along a jog-line 4-4 of FIG. 1, the job portion of the line 44 being shown by a dash-dot line cutting across the orbital shaft, the view showing the position of the orbital shaft relative to the shaft opening in the stationary valve member;

FIG. 5 is a side view of the orbital shaft showing a conical rubbing-limit surface instead of the flat face in FIG. 1;

FIG. 6 is a cross-sectional view taken along the line 6-6 of FIG. 4, but shows a modification thereof in that the rubbinglimit surfaces are conical instead of flat in FIGS. 1 and 4;

FIG. 7 is an enlarged, partial representation of the orbital shaft and the stationary valve member, and shows the relationship between the conical rubbing surfaces of FIG. 6; and,

FIG. 8 is a representation of the relative orbital and rotational movements of the rubbing-limit surfaces.

DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to the drawing, the fluid pressure device in i which my invention may be incorporated, comprises generally a hollow housing 20 having substantially a square cross-section. A mounting flange or end plate 21 may be secured to the left-hand end of the housing. Intermediate the ends of the hollow housing 20, there is provided an annular interval rim 22 which generally separates the hollow housing into a left-hand end compartment and a right-hand end compartment. Rotatively mounted in the left-hand end! compartment is a main shaft 25 having an axis substantially coinciding with the longitudinal axis of the fluid pressure device. A bushing 27 and a rotary valve 28 are mounted in the right-hand end compartment. On the right-hand end of the hollow housing, there is mounted a square stationary valve member 29 by means of suitable screws 30. The rotary valve 28 is adapted to be rotated relative to the stationary valve member 29 for controlling the entrance of fluid to and the exit of fluid from a stator-rotor mechanism 31 comprising a stator 32 and a rotor 33. An end cap 34 encloses the stator-rotor mechanism 33. The entrance of fluid to and the exit of fluid from the stator-rotor mechanism flows through a plurality of fluid openings 40 in the stationary valve member 29 controlled by the rotation of the rotary valve 28. The stator-rotor mechanism 31 and the end cap 34 are secured to the stationary valve member 29 by means of screws 35. Fluid is delivered to and from the housing 20 through a pair of fluid ports 23 and 24. An orbital shaft 36 interconnects the main shaft 25 with the rotor 33 of the statorrotor mechanism 31 and is adapted to transmit torque therebetween. v

The main shaft 25 comprises an enlarged internal portion having a reduced external portion 41 extending axially outwardly of the hollow housing 20 through the mounting flange 21. The enlarged internal portion of the main shaft is supported preferably by tapered roller bearings, generally indicated by the reference character 42. A tightening nut 54 which threadably engages male threads 55 secures the bearings 42 against axial movement upon the main shaft.

The tapered bearings constitute common bearing means for the main shaft and rotary valve. The common bearing means directly support the main shaft 25 and indirectly support the rotary valve 28 through extension drive means comprising a hollow shaft 44 integrally connected to the main shaft. The hollow shaft 44 extends into the righthand compartment and supportingly rotates the rotary valve 28 relative to the stationary valve member 29. The hollow shaft 44 terminates in a male shank 45 which slidably fits within a female socket provided in the rotary valve 28. This connection comprises a nonrotatable connection and rotates the rotary valve upon rotation by the main shaft.

Although not limited thereto, the stator 32 has seven internal teeth and the rotor 33 has six external teeth. The intermeshing teeth upon relative movement therebetween define operating fluid chambers. The rotor has an axis 70 which orbits about'a fixed axis 69 of the stator. The rotor also rotates about its own axis. The orbital shaft 36, which interconnects the rotor 33 and the main shaft 25 is disposed to drive the rotary valve 28 relative to the stationary valve member. The

right-hand end of the orbital shaft 36 has an operative connec- 7 tion with the rotor 33 and comprises male spline teeth 71 fitting within female spline teeth 72 of the rotor. The left-hand end of the orbital shaft 36 has an operative connection with the main shaft 25 and comprises male spline teeth 73 fitting within female spline teeth 74 in the main shaft. Thus, the lefthand end of the orbital shaft 39 is disposed for rotational movements only about the fixed axis 69 of the stator, while the right-hand end is disposed for both orbital and rotational movements, corresponding to the orbital and rotational movements of the rotor 33. FIG. 8 is a general representative of the recurrent path which a point 50 in FIG. 3 makes as the rotor 33 moves within the stator, and is representative of the rubbing action between the rubbing-limit surfaces.

The stationary valve member 29 has first and second side wall means 38 and 39, with the first side wall means 38 held in facing relationship to the inside face of the stator-rotor mechanism. The second side wall means 39 defines a reference plane against which the rotary valve sealingly engages. The reference plane is also identified by the same number as that for the second side wall means. Extending through the stationary valve member 29, is a shaft opening 52 having a reference axis 53 in axial alignment with the stator axis 69 and being substantially perpendicular to the reference plane 39 defined by the second side wall means 39 of the stationary valve member 29. The orbital shaft 36 extends through the shaft opening 52 and has a shaft axis 51 defining an orbit angle with respect to the reference axis 53. The orbital shaft 36 makes a rotational movement about its own shaft axis and an orbital movement about the reference axis 53, the combined movement being generally represented by FIG. 8. The stationary valve member 29 in FIGS. 1 and 4 shows a flat rubbing-limit surface 47 extending outwardly of the shaft opening 52. The flat surface 47 thus resides in the reference plane 39. The rubbing-limit surface 47 on the stationary valve may be characterized as stop wall means. Extending outwardly of the orbital shaft 36, is a shoulder 48 which may be characterized as body portion means and is bodily disposed in the reference plane 39 and is intersected thereby, with a portion thereof leaning into the shaft opening 52. The shoulder or body portion means 48 in FIG. 1 has a flat rubbing-limit surface 49 which may be characterized as abuttable face wall means. The flat surface 49 is disposed substantially perpendicular to the shaft axis 51. In operation, the rubbing-limit surface 49 makes a combined orbital and rotational movement relative to the rubbing-limit surface 47 on the stationary valve and is disposed for abuttable engagement therewith to limit relative axial movement between the male and female spline teeth. Accordingly, the male and female spline teeth 73 and 74 are kept in full axial engagement with each other. The rubbing-limit surfaces in the present application have been changed to a new location from that shown in my abovereferred to patent, whereby the rubbing action is less and provides longer wear life.

In FIGS. and 6, the rubbing-limit surfaces are conical and are identified by the reference characters 57 and 58 to provide a face-to-face contact instead of a peripheral, circumferential line-contact as presented by the flat surfaces in FIGS. 1 and 4. An enlarged representation of the conical rubbing-limit surfaces 57 and 58 is shown in FIG. 7, where it is noted that the tilt at which the rubbing-limit surfaces 57 and 58 contact each other relative to the reference plane 39 is considerably greater than the tilt of the orbital shaft relative to the reference axis 53. In the drawing, the included tilt of the orbital shaft relative to the reference axis 53 is substantially 3, whereas the included tilt of the rubbing-limit surfaces 57 and 58 relative to the reference plane 39 is substantially 12, being approximately four times as great and being a much larger angle than one would ordinarily suspect. The included angle of the tilt of the rubbing-limit surfaces may reside in a range from 3 to 24, but the preferable included angle of the tilt is approximately 12, as shown in FIG. 7.

It is noted that the rubbing-limit surface 58 defines substantially a conically shaped converging female wall looking in a reference direction away from the second side wall means 39 and toward the first side wall means 38 and that the rubbinglimit surface 57 defines substantially a conically shaped converging male wall looking in the same referenced direction. The female wall 58 makes an acute included angle with respect to the reference plane 39 and preferably resides in a range from 3 to 24 The male wall 57 makes an acute included angle with respect to a plane drawn perpendicular to said orbital shaft axis 51 and preferably resides in a range from 3 to 24. The rubbing-limit surfaces are preferably hardened and are well lubricated by the operating fluid to improve the wear qualities.

Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

What is claimed is:

1. Axial limit means for male and female spline teeth which operate as connection means between an orbital shaft and fluid pressure operating means having a side face, said axial limit means limiting the extent that said male and female teeth may axially move relative to each other and comprising side member means having first and second side wall means with said first side wall means held in facing relationship to said side face of said fluid pressure operating means, said second side wall means defining a reference plane, said side member means including a shaft opening extending therethrough, said shaft opening having a reference axis substantially perpendicular to said reference plane, said orbital shaft having an axis defining an orbital angle with respect to said reference axis and extending through said shaft opening, said orbital shaft having a rotational movement about its own shaft axis and an orbital movement about said reference axis, said side member means including stop wall means disposed outwardly of said shaft opening, body portion means extending outwardly of said orbital shaft and bodily disposed in said reference plane and being intersected thereby with a portion thereof leaning into said shaft opening, said body portion means including abuttable face wall means having a combined orbital and rotational movement relative to said stop wall means and disposed for abuttable engagement therewith to limit relative axial movement between said male and female spline teeth.

2. The structure of claim 1, wherein said stop wall means defines substantially a conically shaped converging female wall looking in a reference direction away from said second side wall means and towards said first side wall means, and wherein said abuttable face wall means defines substantially a conically shaped converging male wall looking in said reference direction and defining an acute included angle with respect to a plane drawn perpendicular to said orbital shaft axis.

3. The structure of claim 2, wherein said female wall defines an acute angle with respect to said reference plane and being greater than said orbit angle.

4. The structure of claim 2, wherein the tilt. at which the male and female walls contact each other relative to said reference plane resides in a range from 3 to 24.

5. The structure of claim 1, wherein said stop wall means is substantially flat and resides in said reference plane.

6. The structure of claim 1, wherein said abuttable face wall means is substantially perpendicular to said orbital shaft axis.

7. Axial limit means for male and female spline teeth which operate as connection means between an orbital shaft and fluid pressure operating means having a side face, said axial limit means limiting the extent that said male and female teeth may axially move relative to each other and comprising side member means having first and second side wall means with said first side wall means held in facing relationship to said side face of said fluid pressure operating means, said second side wall means defining a reference plane, said side member means including a shaft opening extending therethrough, said shaft opening having a reference axis, substantially perpendicular to said reference plane, said orbital shaft having an axis defining an orbital angle with respect to said reference axis and extending through said shaft opening, said orbital shaft having a rotational movement about its own shaft axis and an orbital movement about said reference axis, said side member means including stop wall means disposed outwardly of said shaft opening, body portion means extending outwardly of said orbital shaft, said body portion means including abuttable face wall means having a combined orbital and rotational movement relative to said stop wall means and disposed dicular to said orbit shaft axis.

9. The structure of claim 7, wherein said female wall defines an included angle with respect to said reference plane and resides in a range from 3 to 24.

10. The structure of claim 8, wherein said male wall defines an included angle with respect to a plane drawn perpendicular to said orbital shaft axis and resides in a range from 3 to 24. 

1. Axial limit means for male and female spline teeth which operate as connection means between an orbital shaft and fluid pressure operating means having a side face, said axial limit means limiting the extent that said male and female teeth may axially move relative to each other and comprising side member means having first and second side wall means with said first side wall means held in facing relationship to said side face of said fluid pressure operating means, said second side wall means defining a reference plane, said side member means including a shaft opening extending therethrough, said shaft opening having a reference axis substantially perpendicular to said reference plane, said orbital shaft having an axis defining an orbital angle with respect to said reference axis and extending through said shaft opening, said orbital shaft having a rotational movement about its own shaft axis and an orbital movement about said reference axis, said side member means including stop wall means disposed outwardly of said shaft opening, body portion means extending outwardly of said orbital shaft and bodily disposed in said reference plane and being intersected thereby with a portion thereof leaning into said shaft opening, said body portion means including abuttable face wall means having a combined orbital and rotational movement relative to said stop wall means and disposed for abuttable engagement therewith to limit relative axial movement between said male and female spline teeth.
 2. The structure of claim 1, wherein said stop wall means defines substantially a conically shaped converging female wall lOoking in a reference direction away from said second side wall means and towards said first side wall means, and wherein said abuttable face wall means defines substantially a conically shaped converging male wall looking in said reference direction and defining an acute included angle with respect to a plane drawn perpendicular to said orbital shaft axis.
 3. The structure of claim 2, wherein said female wall defines an acute angle with respect to said reference plane and being greater than said orbit angle.
 4. The structure of claim 2, wherein the tilt at which the male and female walls contact each other relative to said reference plane resides in a range from 3* to 24*.
 5. The structure of claim 1, wherein said stop wall means is substantially flat and resides in said reference plane.
 6. The structure of claim 1, wherein said abuttable face wall means is substantially perpendicular to said orbital shaft axis.
 7. Axial limit means for male and female spline teeth which operate as connection means between an orbital shaft and fluid pressure operating means having a side face, said axial limit means limiting the extent that said male and female teeth may axially move relative to each other and comprising side member means having first and second side wall means with said first side wall means held in facing relationship to said side face of said fluid pressure operating means, said second side wall means defining a reference plane, said side member means including a shaft opening extending therethrough, said shaft opening having a reference axis, substantially perpendicular to said reference plane, said orbital shaft having an axis defining an orbital angle with respect to said reference axis and extending through said shaft opening, said orbital shaft having a rotational movement about its own shaft axis and an orbital movement about said reference axis, said side member means including stop wall means disposed outwardly of said shaft opening, body portion means extending outwardly of said orbital shaft, said body portion means including abuttable face wall means having a combined orbital and rotational movement relative to said stop wall means and disposed for abuttable engagement therewith to limit relative axial movement said male and female spline teeth, said stop wall means defining substantially a conically shaped converging female wall looking in a reference direction away from said second side wall means and towards said first side wall means.
 8. The structure of claim 7, wherein said abuttable face wall means defines substantially a conically shaped converging male wall looking in said reference direction and defining an acute included angle with respect to a plane drawn perpendicular to said orbit shaft axis.
 9. The structure of claim 7, wherein said female wall defines an included angle with respect to said reference plane and resides in a range from 3* to 24*.
 10. The structure of claim 8, wherein said male wall defines an included angle with respect to a plane drawn perpendicular to said orbital shaft axis and resides in a range from 3* to 24* . 